Paperboard



FIG. 1 is a perspective view of the paperboard taken from the top and left sides thereof;

FIG. 2 is a top view thereof;

FIG. 3 is a left side view thereof;

FIG. 4 is a right side view thereof;

FIG. 5 is a front side view thereof;

FIG. 6 is a back side thereof; and,

FIG. 7 is a bottom view thereof.

The broken lines in the drawings illustrate portions of a paperboard which form no part of the claimed design. 

CLAIM The ornamental design for a paperboard, as shown and described. 